Use libtracefs as package name to lookup the CFLAGS for libtracefs. This
makes it possible to use the distro specific path as include path for
the header file.

Link: https://lkml.kernel.org/r/20240617-rtla-build-v1-1-6882c34678e8@suse.de

Cc: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Daniel Wagner <dwagner@suse.de>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>